CVE-2026-64368
Vulnérabilité élevée dans Linux (Linux)
Description
In the Linux kernel, the following vulnerability has been resolved: mm/slab: do not limit zeroing to orig_size when only red zoning is enabled When init (zeroing) on allocation is requested, for kmalloc() we generally have to zero the full object size even if a smaller size is requested, in order to provide krealloc()'s __GFP_ZERO guarantees. But if we track the requested size, krealloc() uses that information to do the right thing, so we can zero only the requested size. With red zoning also enabled, any extra size became part of the red zone, so it must not be zeroed and thus we must zero only the requested size. However the current check is imprecise, and will trigger also when only SLAB_RED_ZONE is enabled without SLAB_STORE_USER (which enables tracking the requested size). This means enabling red zoning alone can compromise krealloc()'s __GFP_ZERO contract. Fix this by using slub_debug_orig_size() instead, which is the exact check for whether the requested size is tracked. We don't need to care if red zoning is also enabled or not. Also update and expand the comment accordingly.
Gravité et risque d'exploitation
CVE-2026-64368 obtient un score CVSS de 8.1/10, soit une gravité élevée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.42 %, ce qui la place devant 34.5 % des CVE référencées.
Que faire ?
- Vérifiez si Linux (versions <=6.12.*, <2382971aaaef5bf85a651234c64906f59580b8be, 6.18.39, 9ce67395f5a0cdec6ce152d26bfda13b98b25c01, 0, <=7.1.*, 7.1.4, <7e706d50fa119eead6376bf0ef973e8d73a96030, <=6.6.*, <=6.18.*, <6.2, 6.6.145, <=*, <6256899c3a34674bba6076884aedbba49fc695e4, <0d18ccef142f04433dfb2a0c120cf223d2b8a42c, <648927ceb84021a25a0fbd5673740956f318d534, 6.12.96, 7.2, 6.2) est présent sur votre parc.
- Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
- À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
- Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.
Références
- https://git.kernel.org/stable/c/6256899c3a34674bba6076884aedbba49fc695e4
- https://git.kernel.org/stable/c/7e706d50fa119eead6376bf0ef973e8d73a96030
- https://git.kernel.org/stable/c/2382971aaaef5bf85a651234c64906f59580b8be
- https://git.kernel.org/stable/c/0d18ccef142f04433dfb2a0c120cf223d2b8a42c
- https://git.kernel.org/stable/c/648927ceb84021a25a0fbd5673740956f318d534